prodrive tony Posted August 5, 2007 Posted August 5, 2007 When I had the new TD05 turbo fitted with the new lump last year the mechanic (in very loose terms) said he had the boost turned down by adjusting the actuator (top of turbo) on the arm?? As I'm running a low 0.65 bar of boost []can I adjust slightly by adjusting arm?? If I do it bit by bit then checking by driving , this should be ok should'nt it?? Cheers.
Deano 666 Posted August 6, 2007 Posted August 6, 2007 hi tony, if you need to increase boost pressure, you can adjust the actuator on to the waste gate, you will need to extend the length of the rod, the more tension you put on the gate, the longer it will stay closed, this will give more boost. try 1/4 of a turn to start with, or look and see if there is a mark on the rod from its old setting. [Y]
prodrive tony Posted August 6, 2007 Author Posted August 6, 2007 You are the man, a walking legend [Y] What pressure do you recommend?? 0.9 bar till I get ECU??
granby Posted August 6, 2007 Posted August 6, 2007 Quote You are the man, a walking legend [Y] What pressure do you recommend?? 0.9 bar till I get ECU?? 0.000000000000001 bar [] I'll get my coat
prodrive tony Posted August 6, 2007 Author Posted August 6, 2007 Quote Quote Still do a wagon [] In your dreams []
prodrive tony Posted August 6, 2007 Author Posted August 6, 2007 Dean....Do I remove cir-clip then rotate the end of the arm to make longer and then reattach?? Cheers pal.
HOL Posted August 7, 2007 Posted August 7, 2007 Quote Dean....Do I remove cir-clip then rotate the end of the arm to make longer and then reattach?? Cheers pal. You sure you need to make it longer? On the RS Turbos and GTT's we used to pull it tighter (shorter)to hold the wastegate shut for longer. If I recall, the standard 'preload' was half a hole. The map on your car should be doing this, by bleeding out the boost via your solenoid valve.
prodrive tony Posted August 7, 2007 Author Posted August 7, 2007 I'm just about to test. What do you mean by 'Preload' was half a hole?? Cheers Hol.
prodrive tony Posted August 7, 2007 Author Posted August 7, 2007 Still got 0.7 boost and I inherited a miss fire on way back down A2!! Comes and goes, holds back. Maybe I should put it back.[] Or its just freaky timing?? []
prodrive tony Posted August 8, 2007 Author Posted August 8, 2007 Adjusted back and now got 0.6 bar!!! [8o|] Not mis-firing it seems at the mo....... The rod cant be shortened as its on the wastegate stopper or what I assume is the fully closed position and would be impossible to reattach arm if shortened??????. Heeeeeeeelp[]
granby Posted August 8, 2007 Posted August 8, 2007 Get the thing remapped properly [Y] you know you have to []
Deano 666 Posted August 8, 2007 Posted August 8, 2007 Quote hi tony, if you need to increase boost pressure, you can adjust the actuator on to the waste gate, you will need to extend the length of the rod, the more tension you put on the gate, the longer it will stay closed, this will give more boost. try 1/4 of a turn to start with, or look and see if there is a mark on the rod from its old setting. [Y] sorry i didnt have a turbo unit on my desk at the time, to see if it has to be longer or shorter to hold the gate closed.[:-*]
prodrive tony Posted August 8, 2007 Author Posted August 8, 2007 Yes think I will Granby, just waiting on funds for Apexi........Deano, I can only see it being adjusted longer as its on its stopper.
granby Posted August 8, 2007 Posted August 8, 2007 You've got to mate, you have a bigger turbo and now your trying to up the boost, get it sorted before the engine goes bang
HOL Posted August 8, 2007 Posted August 8, 2007 Quote I'm just about to test. What do you mean by 'Preload' was half a hole?? Cheers Hol. HOL Actuator Tuning 101: The actuator is a mechanical device with a spring to keep it closed, and a pressure induced diaphram opposing it at the other end. Its job is to hold back the wastegate arm and hence the waste 'gate' itself, as shown below: At the boost in the car is increase, the boost in the small pipes leading to actuator are also increased until such a point that it pushes against the force of the spring and opens the gate up, letting any EXTRA boost inducing exhaust gases escape doen the exhaust. In a purely mechanical system, the actuator can be 'fooled' into opening later by bleeding off some of the boost in its supply pipe (a bleed valve). For Example - You can put 2bar into the beginning off the pipe, bleed half out along the way and still keep closed a 1.1bar actuator with only 1 bar at the end. BUT, your car will be bossting to 2 bar.. On a scoob, the boost is actually regulated by the boost solenoid, which is ultimately controlled by the map in the ecu. Although you can fool these by fitting a dawes device (another type of bleed valve). The more boost you run, the stronger spring you need to hold your wastegate shut, as the exhaust gases and boost pressure can open it up on their own - boost creep. What may have happened in your car is that the actuator spring has got weakened and is not holding the actuator arm firm enough. The trick here, as will any spring is to increase its pulling force. This is normally done by making the arm shorter (or longer) depending on the turbo design. When you disconnect the actuator link from the waste gate arm, you should see a half-hole overlap between the two (like a partial eclipse of the moon), whereby you have to stretch the rod a half holes distance to put it on. This is your half hole preload. If this not enogh, then increase the preload until you get the boost you want. Chnaces are your spring IS week, and the story of slacvkening it off, is just a front and no amout of adjusting will help. In such cases you really need a replacement actuator. I hope that makes sense? Sorry I cannot be Scooby specific, but i have never taken my the Turno off my car.
prodrive tony Posted August 8, 2007 Author Posted August 8, 2007 Thanks Hol, really well explained and much appreiciated[Y] My arm is on without any tension (half moon) so will require shortening. I'm probably running the arm with no pre tension now hence low boost. I have also noticed the boost pipe to the actuator is cracking so should be changed. My actuator is new but I may invest in a Forge uprated version[Y] Super advice matey. []
HOL Posted August 9, 2007 Posted August 9, 2007 If the acyuator is new, id keep it. Aftermarket ones are only shiny versions that have interchangeable springs. Not worth the effort in a car that is running less than 2 bar (been there in a 5GTT). Also no really worth it on a Scoob as boost is ECU controlled anyway and you wont ever see it, due to the Turno's position. If you must, rally design in faversham do a cheaper one with changeable springs than Forge. Do change the pipe though, if it has a hole, you have a 'bleed'.
prodrive tony Posted August 9, 2007 Author Posted August 9, 2007 Yeah I've scrapped that idea[Y] Went a drive last night and it felt really good. [] Cant wait to go from 220 bhp to near the 300 mark.....should feel that ok. Just got to change this exhaust gasket on manifold now.......sounds like a fart machine at the mo.
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